Compressor-controlling mechanism



F. D?. HOLDSWORTH. COMPRESSOR CONTROLLING MECHANISM.

APPLICATION HLED mmm, 1917.

1,408,943. Patented Mar. 7, 1922.

Donnas-ooevaa 5 FRED D. HOLD-SWORTH, OF CLAREMONT, NEW HAMPSHIRE, ASSIGNL'R T0 SULLIVAN MACHINERY COMPANY, A CORPORATION F MASSACHESETTS.

COMPRESSOR-CONTROLLING MECHANISM.

Application tiled May 21,

To all whom it may concern:

Be it known that I, FRED D- HoLDswoR'rH, a citizen of the United States residing at Claremont, in the county of bullivan and State of New Hampshire, have invented certain new and useful Improvements in Compressor-Controllin Mechanisms, of' which the following is a full, clear, and exact specification.

My invention relates to compressor controlling mechanisms.

It has for its object to control a, compressor in an improved manner and to provide improved means whereby the compressor is automatically loaded or unloaded in accordance with the requirements of its service. A more speciic object of my invention is to provide improved valve controlling mechanism especially adapted to multi-stage machines, whereby as a result of pressure changes arising from the closure of the main unloader or intake controlling valve, the inlet valves of the compressor are opened to unload the compressor, these valves being thereatl'ter closed as the pressure conditions -again vary. These and other objects of my improved construction will, however, herein'after more fully appear.

In order that my invention may be fully and clearly disclosed, I have illustrated in the accompanying drawings one embodiment which the same may assume in practice.

In these drawingsy Fig. 1 is a side elevation of a compressor equipped With my improvement, portions of the same being broken away to facilitate illustration.

Fig. 2 is an enlarged detail sectional view of the intake controlling valve and its connections, the valve being shown in closed position.

Fig. 3 is a transverse sectional view taken on line 3-3 of Fig. 2. 1

Fig. 4 is aI detail sectional view of one of the pilot valves.

In this illustrative construction, I have shown a multi-stage compressor mounted upon a suitable base and comprising a low pressure cylinder 1 having a piston 2 movable therein and connected through a piston rod 3 With an axially disposed piston 4 in a high pressure cylinder 5. As shown, each of the cylinders 1 and 5 is provided with inlet valves 6 of the suction type and with discharge valves 7 of usual construc- Specication of Letters Patent.

Patented Mar. 7, 1922. 1917. Serial No. 169,971.

tion, only one of each set of valves-being shown for purposes of illustration. Operatively connected between the cylinders is also the usual intercooler 8, and operatively connected to the high pressure cylinder through a suitable connection 9 is a receiver 10. Disposedin the intake 11 leading to the low pressure cylinder is also an unloader valve 12 of usual construction, normally `held open by a spring 13 and adapted to be closed by :fluid pressure through means hereinafter described, or manually by the adjustment of a suitable adjusting mechanism 14.

.In my improved construction, it will be noted that this unloader valve 12 is connected through a connection 15 with the receiver 10, the air supply from the receiver i .valve 19 communicates with a passage 20 leading into a central axially vdisposed chamber 21 disposed within the' chamber 16, wherein the pressure surface of the valve 12 in such a manner as to depress the same and close the intake.

may act upon the upper v As in the usual operation of such an unloader valve, when the receiver pressure rises above a predetermlned point, the same l actuates the valve 19 and admits the receiver pressure tothe chamber 21 so that as a result the main unloader valve 12 is depressed against the pressure of its spring 13 to close the intake 11. Conversely, when the receiver pressure falls below a predetermined level the air in this chamber 21 will he exhausted through the valve 19 to the atmosphere. It will also be noted that in this construction I `have provided a pipe 22 which communicates with the chamber 16 andy acts as a drain for any liquid accumulated therein. i

Obviously, through the operation of the mechanism just described, the intake 11 will be opened or closed in accordance with variations in pressure in the receiver 10. As soon, however, as the valve 12 is closed, it will be obvious that since no air is supplied to the compressor, the continued operation v thereof will result in the progressive formation of a vacuum in the compressor spaces, the vacuum first being formed in those spaces on the inside ol the valve 12 so that practically as soon as the valve^12 is closed the low pressure cylinder will be unloaded. The suctionv valves 6 for the high pressure cylinderwill remain operative, however, and it is desirable for them to do so for a short time tor reasons of eiciency, in order that the air then in the compressor may be delivered to the receiver. In my improvement, l have provided improved means whereby these last mentioned suction valves may be lifted Atrom their seats, the progressive drop in pressure in the compressor following from lthe closure of the intake valve 12 being utilized in bringing about this movement of the suction valves.

As shown, these suction vvalves 6 of the high pressure cylinder are provided with the usual spring pressed valve stems, and beneath the same are located suitable pistons or plungers 23 movable in suitable cylinders 24, of which only oneis shown for purposes ot illustration. These cylinders 24 are in turn connected through a pipe connection 25 with a second pilot valve 26 operatively connected to the chamber 16 through a pipe connection v27 and. also connected through a pipe connection 28, communicating with a removable dome or cover member29 on the valve 26, with a point in the compressor where the pressure is reduced a short time after closure of the intake valve 12. vHerein, l have shown this connection 28 to bemade to a chamber 30 disposed within oneot the pillar supports 31 for the high pressure cylinder and communicating in the usual'nianner with the intercooler 8 so that the pressure in this chamber varies with the pressure in the intercooler. Obviously, however, if quite such a long delayed unloading of the high pressure cylinder is not desired, this connection may be made at a point at the compressor side of the yintake valve 12 through a suitable connection 32, and l have accordingly shown the same connected to each ot these points, suitable controlling valves 33, 34 being provided in the connections 28. 32 so that upon opening its valve either of the same may be used, the other then being cutout by closing its valve. A l

Obviously. as a result of this construction.. when either the pressure in the chamber 30 or at the compressor side of the intake controlling valve 12 drops below a predetermined amount.. the pilot valve 26 will be operated in such a manner as to open communication 'from the receiver 10 to the chamber 17 and through the pipe connection 27 to the connection 25 and the pistons or plungers 23 'for operating the suction inlet mosaics valves 6 of the high pressure cylinder. As a result of the fluid supply through these connections, these valves 6 will be lifted from their seats in such a manner as to unload the compressor. When, however, the receiver pressure -falls to such an extent as to cause the unloader valve 19 to be operated in a well known manner to exhaust the pressure from the space 2-1 above the intake controlling valve 12, this valve 12 will be opened by its spring 13 in such a manner as to permit the pressure in the compressor to be built up. Thereupon, due to the increase in pressure supplied through the connection 28 to the top of the pilot valve 26, that valve will be operated in such a manner as to open the connection 25 to the atmosphere in a well known manner through ports 35, thereby exhausting the air from beneath the plungers 23 and permitting the suction valves 6 ot the high pressure cylinder to seat and load the compressor so that it may again supply rpressure liuid to the depleted receiver.

Theunloadingmechanismincludingthe ilot valve 26 and its dome-shaped cover 29,w ich herein is connectible either to the chamber y3() or the compressor side of the intake coutrolling valve 12. has been described in my co-pending application Serial No. 134,452, tiled Dec. 1, 1916, but in order that the operation of the same in my present invention may be clearly understood, the description of this mechanism will be repeated herein, it vbeing understood that save Jtor the cover 29, the valve 19 may be ot the same construction as the valve 26. This valve 26 is shown in an enlarged View in Fig. 4. As illustrated therein. it preferably comprises a suitable casing having a diaphragm 36 disposed across a chamber 37 in its bottom. To this chamber 37 air at receiver pressure is admitted 'from the connection 27 communieating with the receiver 10 through the chamber 16. Disposed below this diaphragm 36 in this chamber, is a vertically disposed spring pressed hollow plunger 33 having oppositely disposed ports 39 at its upper end communicating with the chamber 37. Disposed adjacent the open lower end of this member 38 is also a ported disk valve 40 normally held in elevated position by a spring 41, in such a manner as normally to engage the lower end of the depressed plunger 38 and thereby close communication between thc receiver and a port l2 leading to the connection 25. As usual. a series of ports communicating with the ports 35 which lead to the atmosphere, is also disposed adjacent the valve t0 and, due to the lll() action ot the spring 4l, the ports in the Y phragm and acting on the opposite surface thereof, is a plunger 44, normally held in depressed position by a coiled spring 45 which acts between the plunger and an upper adjustable cap member 46 having a port 47 therein communicating with the space within the'dome member 29. In practice, this spring 45 is of sufficient strength when added tothe pressure in the compressor to the ports in .the valve member 40 through the opening 42, to the connection 25 in such a manner as to raise the valve plungers 23 of the high pressure inlet valves 6 and lift the latter from their seats to unload that cylinder. Conversely, when the pressure in the compressor is built up, as afterthe intake controlling valve is again opened, the diaphragm 36 is depressed and the plunger 38 again lowered to normal position to open communication between the ports 35 and the connection 25 and thusl cause the air beneath the plungers 23 to be exhausted so that the `valves 6 of the high pressure cylinder may seat and thereby load that cylinder.

In my ,improved construction, it will be vnoted that through the provision of the dome 29 and the connection of the same to the chamber 30 or to the com ressor lside of the valve 12', I have provide means whereby this valve mechanism may be made responsive to the variations in the pressure within the compressor, and therefore operate to control the low throughthe connection 25 in accordance with variations in pressure arising from the opening or closing of the intake. In this c `nstruction it will further be noted that, as distinguished from the co'nstruction shown in m .previous application mentioned above, I ispense with separate inlet valve actuating plunger mechanism for the low pressure cylinder, and utilize a pilot valve to control the main unloader valve or intake controlling valve.

In the earlier application among other features, meanstor effecting a stepped unloading of the cylinders of a multiple cylinder compressor is broadly set forth and claimed, including means for controlling the loading and unloading of one stage controlled by eii'ects produced by the loading or unloading of another, or means for unloading the low pressure stage of a compressor, and means for unloading or reloading a higher pressure stage governed as to both its functions by the combined effects of the discharge pressure of that stage during normal loaded running and the pressure in said compressor at a point between the suction side of that stage and the intake of said compressor. Therein I also claim cer- .tain sub-combinations relating to the structure of the H. P. pilot control, along with other features. L

While I have in this application specifically `described one embodiment which my invention may assume in practice, it is to be `understood that the same is not limited thereto,but may be modified and embodied in various other forms without departing' from its spirit, it being my intention to include all such modifications within the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

l. In combination, a multistage compressor, and means for unloading the several stages of said compressor at variable intervals comprising means for unloading one of said stages, and means for subsequently unloading another of said stages including a control member actua-ted by .compressor dis- .charge pressure and operative in opposite posit1ons vthereof to eilect loading and unloading ofsaid last mentioned stage, -said member being movable substantially instantaneously between its operative positions, and means for varying the instant of movement kof said member.

2. In combination, a compressor having a -plurality of stages, unloading means cooperating' with each of said stages, meanscooperating with the unloadingmleans for one of said stages for delaying the opera- .tionthereoi after the operationof said other unloading means including a plurality of connections with said compressor beyond said lirst mentioned unloading means, and means for selectively controlling said connections to vary the delay in operation.

3. In combination, a compressor having a plurality or' stages, unloading mechanisms cooperating with each of said stages, means responsive to receiver pressure for controlling the operation of one of said mechanisms, means for controlling thev operation of another of said mechanisms -responsive to receiver pressure and having a connection with said compressor at a point beyond s aid first mentioned unloading means, and means tor varying said point of connection.

4. In combinatmn, a compressor having a plurality of compression chambers, unloading mechanism' for each of said chambers, contro-lling means each independent of the other for each of said unloading means and having a common source of operating medium, and means for causing said means to operate sequentially and with variable intervals between their operations.

5. In combination, a multistage compresser having e plurality or? compression chambers snel en intake, intake controlling mechanism, inlet valve mechanism for sn comlpresison chamber constituting s stage above the iirst stage, 'snol controlling nieoho,n nism foi saitl inlet valve mechanism cono.m prising ineens oilierstive to render ,the letter inoperative `including e controlling velve operated by compressordischnrge pressure and controlled by vsrietions in. pressure arising from the closure oiseiol intelro 6. ln coinbinstion, e rcompressor heving o plurality of compression clienibers ond en intake, intzilre closing mechanism, end sinto-A rnziticully zicting means including s plurality of inlet valves controllecl by vorietions in pressure arising from the closure oi ssicl intake enti operated; by receiver pressure for unloading; one ci seicl compression chenibers p 7. ln combination, s, compressorheving e plurality oi compression chambers :incl an intake, intslre closing mechanism, enclsuto mnticslly noting ineens operated; by ter'- ininel pressure encl controlled by variations in pressure arising from the closure of seid. intnlre to eiliect e cleleyecl unloscling ol one of seid chemio-ers.

El. ln combination, s compressor heving s plurality ott velveci compression chambers and on intz'ilre, intake closing ineens eiiective upon closure to unlozicl one oi seid. cheinbers, end ineens opersterl by terininsl pressure and controlled by ,vsrietions in pressure arising trein closure ol solo intelre for effectingr e relatively retor'olecl nnlosding oi 'the other compression chamber.

9, ln combination, e conipressor having s plurality ci valved compression clioinbers enel en intslre, inta-ire closing ineens eileotive upon closure to nnloecl one olf sind chambers, i

ineens opereterl by terminal press lre :incl controlled by variations in pressure arising from closure of esiti intelre for eilectinge relatively retarded unloading ci the other compression chamber, end ineens for verying the oegree of reterflstion.

lll, e.. compressor controlling mechenisin, the combination including s, ninlti- Stege compressor hsving e plurality oit com,- pression chambers and en intslre,inlet velves for the high compression chamber thereof, intslreclosing mechanism, sini ineens responsive to n chenge in pressure condition arising from the closure of seni intoke closing inechenisin for controlling sciiti inlet p valves.

ll. ln s compressorv controlling meche- "nisrn, thefcombination including;- n inulti stage compressor having e plurality of coni.- ression chambers end en intake, suction, in-

et valves lor the high compression cheinberthereof, intake closing niechsnisni, enti ineens yresponsive to s change in.' pressure condition arising from the closure of ssicl sponsive to e clisnge in pressure condition arising 'from the closure of senti intelre clos ing mechanism forA controlling seid inlet velves by the action of compressor clischsrge pressure i3, lingo compressor controlling noechenisin, the combination including o moltistsge compressor having e plurality of com pression chambers end en intel/re', suction inv let velves tor the high compression chem-ber thereoif, intolre closing ,ineclienisrm enti ineens responsive to e che-nge in pressure condition arising from tbe closure of seiol intake closing rnechenisni for nnseoting ssifl suction inlet valves by the ection oi" cornpressor discharge pressure.

le, lin combination, e, compressor heving on intzilre, s. receiver, on intelre controlling ineens provided with en intake controlling velve and e plurality oi chambers, one of seicl cheinbers ,communicating with seid valve and the other with seid; receiver, en@ pressure responsive mechanism controlling the supply snel exhaust of pressure iluio reletive to the chamber commnniceting with seii valve end locsteol` exterior to solo. lest nientioneii cheminer.

i5., ln combination, e compressor having en intake, si receiver, en intelre controlling ineens provicleti with en intslre control valve, s plurality of chambers, one oi seiol chembers communicating with seid; velveend the other with seid receiver, drainage ineens lor seicl lestnientionecl cheinber, endpressure responsive vslve mechanism controlling et connection between seid chombers end located exterior to erich of thorn.l

iti ln combination, e compressor having en intake, s receiver, eno intolre controlling ineens comprising s casing heving e plurality of chambers, an intuire controlling volvo in one of seid chambers, e cominunicstion between one of seid chambers end the receiver, ancl evconnection between seni lest nernccl chsinberand ssicl valve contsining chernber, seid connections being provided with e receiver pressure responsive controlling velve., f i

i7., combination, s compressor having en intake, s receiver, en inteke controlling vslve provirled with si. plurality oi concentric chambers one communiceting with seid valve sn the other with seid receiver, end valve niechenisrn responsive to receiver pressure controlling the pressure conditions in the clieinber cornnounicsting `with Vsziicl velve.

15.8... ln combinetion, s compressor having llo ist

high and low pressure cylinders and an intake', a receiver, intake closing mechanism responsive to receiver pressure, inlet valves for a high pressure cylinder, means for unseating said inlet valves including a connection to the receiver, and means controlling said connection responsive to pressure conditions arising from closure of the intake.

19. lin a compressor controlling mechanism, the combination including a multistage compressor having an intake, inlet valves for the high pressure cylinder thereof, intake closing mechanism, pressure actuated plunger mechanism for actuating said inlet valves, and means responsive to a change in pressure conditions arising from the closure of said intake closing mechanism for supplying pressure iluid to said plunger mechanism.

20. ln a compressor controlling mechanism, the combination including a compressor having high and low pressure cylinders, a receiver connected to said compressor, intake controlling mechanism responsive to receiver pressure, inlet'valves for the low pressure cylinder communicating with the' compressor side of said intake controlling mechanism. inlet valves for a high pressure cylinder, means for subsequently unloading said high pressure cylinder including a connection between iaid inlet valves of said high pressure cylinder and said receiver, and means for controlling said connection responsive to changes in pressure conditions in said compressor. y

2l. ln combination, a compressor having high and low pressure cylinders, a receiver connecteltd to said compressor, compressor intake con rolling mechanism connected to said receiver, inlet valves for a high pressure cylinder, and means for actuating said valves to unload said cylinder including a pilot valve operatively connected to said receiver through said intake controlling valve mechanism` and to `the compressor spaces at a point on the compressor side of said intake controlling mechanism.

22. In a compressor controlling mechanism, the combination including a' multistage compressor having an'f intake, inlet valves for the high pressure stage thereof, intake closing mechanism, pressure actuated mea-ns for unseating said inletvalves, means responsive to variations inypressure arising Ifrom closure of said intake closing mechanism controlling the pressure conditions in said'pressure actuated means, and pressure responsive means controlling said intake closing mechanism.

23. ln acompressor controlling mechanism, the combination including a compressor havinghigh and low pressure cylinders, a receiverfintake controlling mechanism for said compressor including a valve havin a chamber communicating therewith an a chamber communicating 'with` the receiver, a

connection between said chambers, means in' said connection responsive to recelver pressure ncontrolling the pressure conditions in the chamber communicating with said valve, suction -inlet valves for the low pressure cylinder, suction inlet Valves for a high pressure cylinder, plunger mechanism for unseating said last mentioned valves, pressure Huid connections between said plunger mechanism and said receiver, and mea-nsresponsive to pressure conditions in the compressor arising from closure oi said intake controlling valvecontrollin the pressure conditions in said pressure fluid connections. ,k

24. lin a` compressor controlling mechanism, the combination including a multistage compressor having a plurality of cylinders and an intake, inlet valves for the high pressure cylinder thereof, intake closing mechanism,l pressure'actuated plunger mechanism for afctuatingsaid inlet valves, f

and means responsive either to a change in pressure conditions beyond the cylinder arising'lrom the closure "of said iiitake closing mechanism, or to pressure at a point beyond said intake closing mechanism,

low pressure v for supplying pressure iiuid to said plunger Y' mechanism. n

Q5. ln combination, a compressor having high and low pressure cylinders, intake c ontrolling mechanism, inlet valve mechanlsm for the low pressure cylinder thereof, inlet valves :tor the high pressure cylinder, and

means responsive either to pressure changes in said compressor beyond the low pressure cylinder. arising from closure ot' said intake controlling mechanism or to the pressure changes inv said inlet forcontrolling certain of said inlet valves. I

' 26. ln a compressor controlling mechanism, the combination including a multicylinder compressor having an intake, inlet valves for the high pressure cylinder thereof..

intake closing mechanism, pressure actuated means for unseating said inlet valves, meansv responsive either to variations i n pressure beyond one of said cylinders arising from closure of said intake closing mechanism or to pressurevariations in said intake, .tor controlling the pressure conditions in said pressure actuated means, and pressure responsive means controlling said intake closing mechanism.

27. ln a combination, a. multi-cylinder compressor having an intake, intake closing mecaanism, automatically acting means controlled by variations in pressure between tw o of said cylinders or in said intake and arising from the closure of said intake rcr progressively unloading said 'compressor cylinders, and manually operable means for subjecting said automatically acting means to either of said pressures.

28. ln combination, a multi-cylinder compressor having an intake, intake closing pressoito vary the operation oi the control-V ling meansn A30. ln combination, a compressor having a plurality of compression chambers, unloading mechanism 'for each of the chambers, means 'for effecting variable sequential operation of said unloading mechanism comprising control' means :tor each ot said mechanisms each controllable by the same mediumL as 'the other, and means governed by the et- 'ects produced at various points in said compresser by the operation ot one ot said control means tor controlling the operation of the other.

3l. ln combination, a multistage compressor having a plurality ot compression chambers and an intake, intake controlling mechanism, inlet valve mechanism for a stage above the lirst, means, tor rendering said ,inlet valve mechamism inoperative, and

means tor unloading the stages of said compressor sequentially comprising a plurality oit compressor discharge pressure actuated control valves, one of said valves controlling said intake controlling mechanism and another controlling the means 'for rendering said inlet valve operating mechanism inoperative, said last mentioned valve being provided with control mechanism governed by changes in pressure conditions in the compressor arising from operation ol3 said intake control mechanism.

32, ln an unloadingmechanism ttor compressors, a plunger movable to unload the compressor, fluid pressure control means tor said plunger including a valve, a diaphragm, a spring, said diaphragm and spring normally holding said valve closed, and connections from the opposite sides of said diaphragm respectively to a space wherein a subeatmospheric pressure exists during running o't the compressor unloaded, and a space connected with the discharge side of the compressor.

33, ln a compressor controlling mechanism,'a valve controlling piston, means for controlling the movements of the latter including a valve, a connection with a source ot compressor discharge pressure, a connection with a space wherein a sub-atmospheric pressure exists when the compressor is run unloaded, a diapli agie operatively engaging said valve, and a spring tending to force said diaphragm in a direction to close said valve, said tiret mentioned connection com4 municating with the side ot' said diaphragm toward said valve and said second mentioned connection with the opposite side of said diaphragm.

ln testimony Whereot l adir. my signature.

FRED l). HLDSWRTH. 

